IOIO Appendix V.
through lever M, but when the cage reaches its highest or lowest
position the pressure water is cut off automatically at valve L by
the striking of tappets such as P P, and the load is received on
buffers Q Q when at lowest position. The pipe R transmits
pressure water to the power cylinder, entering at T ; and the pipe
u u connects the displacement cylinder v with the lift cylinder w.
As mentioned, the pressure of the displacement water will depend
upon the load, which varies with the passengers, the minimum
being somewhat under the weight of lift ram and cage. A relief
valve s is placed upon pipe u, and as the water in u gets lost by
leakage and the weights H fall too low, the valve x is automatically
opened, admitting pressure water from R to cylinder y through
pipe Y, wherein is a non-return valve.